In inflating vehicle tires, particularly due to the necessity in many instances of the driver having to do the inflating himself, and the usual situation, being without a tire gauge or at least without a reliable tire gauge, both over inflation and under inflation are experienced. It is the object of this invention to provide a tire gauge that will be mounted on the tire valve and that will prevent over inflation so that the user may apply air to the tire until the clear sound of air escaping from the guide indicates that maximum inflation has been reached. This is a modification of applicant's U.S. Pat. No. 3,910,305, this application covering a flexible o-ring for the expanding means, which may be of any predetermined Shore Durometer hardness to provide means for use of the inflation guide on a variety of tires by merely changing said o-ring.